Extremely useful commands:

• General usage:

  1. To find size of file : stat -c %s <file_name>
  2. To find number of lines in file : wc -l <file_name>
  3. To read a long file gradually from top : more <file_name>
  4. To show the whole contents of a file : cat <file_name>

• Advanced usage:

  1. To find disk parameters : hdparm -options <disk_name>
     1. To check how fast disk can be accessed use -t for general access and -T for cached access.